Armed police were stationed at the Polish Embassy in Moscow on Tuesday, after Polish nationalists attacked the Russian Embassy in Warsaw and clashed with police during an annual Independence Day march.
Polish police detained 32 protesters, including three who are suspected of trying to climb the Russian Embassy's fence and of throwing firecrackers at the building, police spokesman Mariusz Sokolowski said.
In an apparent measure against retaliatory attacks by Russian nationalists, Russia beefed up security by sending additional police to guard the Polish Embassy in Moscow, RIA Novosti reported Tuesday.
The rally in Warsaw, commemorating the day Poland gained independence at the end of World War I in 1918, turned violent after a few dozen youths, most of them wearing face masks, broke off from the main procession to attack a squat occupied by left-wing radicals and set cars on fire.
Riot police moved in but rioters lobbed stones and firecrackers at them. Police responded with rubber bullets, truncheons and pepper spray, Sokolowski said, Reuters reported.
When the march reached the Russian Embassy a section of the crowd threw firecrackers, set upon a guard booth, and tried to get over the fence.
This year's Independence Day march took a violent turn as firecrackers were set off outside the Russian Embassy in Warsaw. (YouTube / Lukasz Mezyk)
Russia and Poland have a history of troubled relations marked by conflicts over territory and the Russian Embassy has been held up by some Poles as a symbol of repression during Soviet times.
Riot police blocked off the building, and the crowd later moved on.
Five police officers had to be taken to hospital as a result of the clashes.